Patents by Inventor Eiji Mayumi

Eiji Mayumi has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8330315
    Abstract: Magnetic poles are arranged such that the N pole and the S pole alternate in a circumferential direction. Two N poles face each other with an interval of 180° therebetween, and two S poles face each other with an interval of 180° therebetween. Each of the magnetization center of a North magnetic pole and the magnetization center of a South magnetic pole is positionally shifted from the center position between the magnetization centers of two magnetic poles of the other polarity located on opposite sides of the North or South magnetic pole. The magnetization centers of the magnetic poles are disposed in such a manner as to be positionally shifted from geometric centerlines. Brushes are disposed along the respective geometric centerlines. The magnetization centers of two adjacent magnetic poles are positionally shifted toward or away from each other by the same shift angle ? with respect to the respective geometric centerlines.
    Type: Grant
    Filed: October 17, 2008
    Date of Patent: December 11, 2012
    Assignee: Mabuchi Motor Co., Ltd.
    Inventors: Eiji Uenishi, Eiji Mayumi
  • Patent number: 8258661
    Abstract: A motor includes a tubular housing having flat side walls along each side of rectangular joined with each other by joining sections, a magnet, having magnet poles in the jointing section, disposed along the inner peripheral surfaces of the housing, a shaft inserted along the axis of the housing, an armature fixed to the shaft in such a position as to be opposite to the magnet, a commutator mounted on the shaft, a carbon brush in sliding contact with the outer peripheral surface of the commutator, and electrical components provided within the housing. The electrical components in the longer direction are arranged such that they are not parallel with all the sides of the housing.
    Type: Grant
    Filed: May 12, 2010
    Date of Patent: September 4, 2012
    Assignee: Mabuchi Motor Co. Ltd.
    Inventors: Hiroshi Yamazaki, Eiji Mayumi
  • Publication number: 20100320854
    Abstract: A motor includes a tubular housing having flat side walls along each side of rectangular joined with each other by joining sections, a magnet, having magnet poles in the jointing section, disposed along the inner peripheral surfaces of the housing, a shaft inserted along the axis of the housing, an armature fixed to the shaft in such a position as to be opposite to the magnet, a commutator mounted on the shaft, a carbon brush in sliding contact with the outer peripheral surface of the commutator, and electrical components provided within the housing. The electrical components in the longer direction are arranged nonparallely with all the sides of the housing.
    Type: Application
    Filed: May 12, 2010
    Publication date: December 23, 2010
    Applicant: MABUCHI MOTOR CO. LTD.
    Inventors: Hiroshi Yamazaki, Eiji Mayumi
  • Publication number: 20100270886
    Abstract: Magnetic poles are arranged such that the N pole and the S pole alternate in a circumferential direction. Two N poles face each other with an interval of 180° therebetween, and two S poles face each other with an interval of 180° therebetween. Each of the magnetization center of a North magnetic pole and the magnetization center of a South magnetic pole is positionally shifted from the center position between the magnetization centers of two magnetic poles of the other polarity located on opposite sides of the North or South magnetic pole. The magnetization centers of the magnetic poles are disposed in such a manner as to be positionally shifted from geometric centerlines. Brushes are disposed along the respective geometric centerlines. The magnetization centers of two adjacent magnetic poles are positionally shifted toward or away from each other by the same shift angle ? with respect to the respective geometric centerlines.
    Type: Application
    Filed: October 17, 2008
    Publication date: October 28, 2010
    Inventors: Eiji Uenishi, Eiji Mayumi
  • Publication number: 20090100948
    Abstract: A rectilinear-motion actuator includes a motor, a reduction gear mechanism coupled with a motor shaft of the motor, and a rectilinear, reciprocative motion mechanism for converting a rotary motion of a last-stage gear of the reduction gear mechanism to a rectilinear, reciprocative motion. The last-stage gear has a pin provided thereon which is offset from its center of rotation. The rectilinear, reciprocative motion mechanism includes a movable plate having a slit and allowing the pin to move within the slit. The slit is arranged orthogonally to the axis of the motor shaft. The longitudinal center of the slit is located on a line in parallel with the motor shaft axis and passing through the center of the last-stage gear. The axis of reciprocative motion of the movable plate is offset from the line passing through the center of the last-stage gear in a direction away from the motor shaft.
    Type: Application
    Filed: September 30, 2008
    Publication date: April 23, 2009
    Inventors: Takashi USHIKU, Eiji MAYUMI
  • Publication number: 20080015084
    Abstract: In a longitudinal motion actuator, one pinion is fixed to a motor output shaft, and a plurality of transmission mechanisms having the same configuration are provided. Each of transmission mechanisms is configured so that both ends of a lead screw to which a gear engaging with the pinion is fixed are rotatably supported by bearings. A movable nut provided with a plurality of threaded holes engaging with thread grooves in the lead screws of the plurality of transmission mechanisms is provided, and when the motor is rotated, the lead screws are rotated in the same direction via the pinion and the gear, by which the movable nut is driven longitudinally.
    Type: Application
    Filed: July 10, 2007
    Publication date: January 17, 2008
    Inventors: Eiji MAYUMI, Takashi USHIKU
  • Patent number: 7095148
    Abstract: A stepping motor includes a rotor with a permanent magnet, a rotary shaft extending from the rotor and a stator placed around the rotor. The stepping motor comprises a stator core placed on one end section in a motor axial line direction of the stator, a bearing plate that includes a bearing for rotatably supporting the rotary shaft and is placed at an end section of the stator adjacent to the stator core, and an end plate fixed to an end surface of the stator core on an outer circumference side of the bearing plate. The stator core includes a plurality of salient poles that bend in the motor axial line direction at an inner circumferential edge of the stator core to oppose the permanent magnet, and concave sections that recede in the radial direction and formed between the bent parts of the salient poles.
    Type: Grant
    Filed: October 9, 2003
    Date of Patent: August 22, 2006
    Assignee: Sankyo Seiki Mfg. Co., Ltd.
    Inventor: Eiji Mayumi
  • Publication number: 20050225185
    Abstract: A stepping motor includes a rotor with a permanent magnet, a rotary shaft extending from the rotor and a stator placed around the rotor. The stepping motor comprises a stator core placed on one end section in a motor axial line direction of the stator, a bearing plate that includes a bearing for rotatably supporting the rotary shaft and is placed at an end section of the stator adjacent to the stator core, and an end plate fixed to an end surface of the stator core on an outer circumference side of the bearing plate. The stator core includes a plurality of salient poles that bend in the motor axial line direction at an inner circumferential edge of the stator core to oppose the permanent magnet, and concave sections that recede in the radial direction and formed between the bent parts of the salient poles.
    Type: Application
    Filed: October 9, 2003
    Publication date: October 13, 2005
    Inventor: Eiji Mayumi
  • Patent number: 6762530
    Abstract: A motor has a stator with a simplified structure having a stator section including at least two core pairs. Each of the core pairs includes inner and outer cores. Coils are wound around the core pairs. A case made of a magnetic material covers the coils in a manner that the case more securely comes in contact with the inner cores and the outer cores. The case is welded to at least the inner cores to securely form independent magnetic circuits.
    Type: Grant
    Filed: February 6, 2001
    Date of Patent: July 13, 2004
    Assignee: Sankyo Seiki Mfg. Co., Ltd.
    Inventor: Eiji Mayumi
  • Patent number: 6707196
    Abstract: A motor includes a rotor equipped with a magnet magnetized in multiple poles, a stator yoke having claw poles with plural pole teeth disposed opposing to one another and arranged in a cylindrical shape extending in an axial direction and around an outer periphery of the rotor in a circumferential direction, a bobbin formed from a coil wound around the stator yoke, and a cylindrical motor case that houses the rotor, the stator yoke and the bobbin. The cylindrical motor case is formed from conductive material and uses as at least a part of the yoke. The motor case defines generally parallel planes tangential to an outer periphery of the coil, and has side wall sections extending in close proximity to the parallel planes and defining plane opening sections, and a part of an outer peripheral surface of the coil of the bobbin protrudes from the opening sections.
    Type: Grant
    Filed: February 5, 2002
    Date of Patent: March 16, 2004
    Assignee: Sankyo Seiki Mfg. Co., Ltd.
    Inventor: Eiji Mayumi
  • Patent number: 6700261
    Abstract: A motor has a stator including a coil bobbin with winding sections to be wound by windings and a terminal section. The terminal section outwardly protrudes in a radial direction of the coil bobbin and has fixed protruded terminal pins that are to be connected to winding start sections and wiring end sections of the windings. A curled case is placed over an exterior of the windings of the stator. The curled case has end sections in the peripheral direction and an opening section defined by the end sections of the curled case. The terminal section protrudes through the opening section, and an opening angle of the opening section is less than one half of the entire periphery of a circle.
    Type: Grant
    Filed: May 23, 2001
    Date of Patent: March 2, 2004
    Assignee: Sankyo Seiki Mfg. Co., Ltd.
    Inventor: Eiji Mayumi
  • Publication number: 20040021375
    Abstract: A stepping motor includes a ring-shaped stator core having a plurality of pole teeth erected from an inner circumferential edge portion, a coil winding wound around the pole teeth and a terminal pin part to which a terminal end of the coil winding is wound around. The terminal pin part is integrally formed and extended from the stator core and an entire surface of at least the terminal pin part of the stator core is covered with an insulating layer.
    Type: Application
    Filed: June 24, 2003
    Publication date: February 5, 2004
    Applicant: SANKYO SEIKI MFG. CO., LTD.
    Inventor: Eiji Mayumi
  • Patent number: 6596215
    Abstract: A stepping motor having a rotor consisting of a permanent magnet magnetized such that N poles and S poles are alternately arranged in the hoop direction, stator cores with pole teeth oppositely disposed on the outer peripheral surface of the rotor, and a coil bobbin integrally containing the stator cores as the result of resin molding and being used for supporting a coil wound thereon. In the stepping motor, holes are formed in the coil bobbin, and the holes range from an outer wall of the coil bobbin to the outer peripheral surfaces of the pole teeth. In the stage of resin molding, the dies are brought into contact with the pole teeth by the utilization of the holes, thereby preventing the pole teeth from being declined in the radial direction, and securing a satisfactory rigidity of the coil bobbin.
    Type: Grant
    Filed: September 20, 2001
    Date of Patent: July 22, 2003
    Assignee: Kabushiki Kaisha Sankyo Seiki Seisakusho
    Inventors: Eiji Mayumi, Yasuhiro Ota, Kazuyo Okajima
  • Patent number: 6541886
    Abstract: A motor comprises a stator, a rotor being arranged in and facing said stator, an urging member which urges a center rotation shaft of the rotor in an axial direction, and a bearing which rotatably holds the rotor at a predetermined position while receiving an urging force by the urging member. The stator is provided with a resin coil bobbin made by insert molding and integratedly assembled with a metal stator core. The stator core is arranged in and faces the rotor and forms a magnetic circuit therewith. The coil bobbin is arranged at the end side of the rotor. A holding portion is integratedly formed, the holding portion holds the urging member so as to urge the rotor to the bearing side. A curling base is fitted in. The curling base is formed such that a flat plate-shaped metal plate is rounded from outside of a winding wound by the electric coil bobbin in the circumference direction of the stator.
    Type: Grant
    Filed: June 12, 2001
    Date of Patent: April 1, 2003
    Assignee: Sankyo Seiki Mfg., Co. Ltd.
    Inventor: Eiji Mayumi
  • Publication number: 20020140303
    Abstract: A motor includes a rotor equipped with a magnet magnetized in multiple poles, a stator yoke having claw poles with plural pole teeth disposed opposing to one another and arranged in a cylindrical shape extending in an axial direction and around an outer periphery of the rotor in a circumferential direction, a bobbin formed from a coil wound around the stator yoke, and a cylindrical motor case that houses the rotor, the stator yoke and the bobbin. The cylindrical motor case is formed from conductive material and uses as at least a part of the yoke. The motor case defines generally parallel planes tangential to an outer periphery of the coil, and has side wall sections extending in close proximity to the parallel planes and defining plane opening sections, and a part of an outer peripheral surface of the coil of the bobbin protrudes from the opening sections.
    Type: Application
    Filed: February 5, 2002
    Publication date: October 3, 2002
    Inventor: Eiji Mayumi
  • Publication number: 20020047383
    Abstract: A motor has a stator including a coil bobbin with winding sections to be wound by windings and a terminal section. The terminal section outwardly protrudes in a radial direction of the coil bobbin and has fixed protruded terminal pins that are to be connected to winding start sections and wiring end sections of the windings. A curled case is placed over an exterior of the windings of the stator. The curled case has end sections in the peripheral direction and an opening section defined by the end sections of the curled case. The terminal section protrudes through the opening section, and an opening angle of the opening section is less than one half of the entire periphery of a circle.
    Type: Application
    Filed: May 23, 2001
    Publication date: April 25, 2002
    Inventor: Eiji Mayumi
  • Publication number: 20020036433
    Abstract: A stepping motor having a rotor consisting of a permanent magnet magnetized such that N poles and S poles are alternately arranged in the hoop direction, stator cores with pole teeth oppositely disposed on the outer peripheral surface of the rotor, and a coil bobbin integrally containing the stator cores as the result of resin molding and being used for supporting a coil wound thereon. In the stepping motor, holes are formed in the coil bobbin, and the holes range from an outer wall of the coil bobbin to the outer peripheral surfaces of the pole teeth. In the stage of resin molding, the dies are brought into contact with the pole teeth by the utilization of the holes, thereby preventing the pole teeth from being declined in the radial direction, and securing a satisfactory rigidity of the coil bobbin.
    Type: Application
    Filed: September 20, 2001
    Publication date: March 28, 2002
    Applicant: KABUSHIKI KAISHA SANKYO SEIKI SEISAKUSHO
    Inventors: Eiji Mayumi, Yasuhiro Ota, Kazuyo Okajima
  • Publication number: 20020024265
    Abstract: A motor comprises a stator, a rotor being arranged in and facing said stator, an urging member which urges a center rotation shaft of the rotor in an axial direction, and a bearing which rotatably holds the rotor at a predetermined position while receiving an urging force by the urging member. The stator is provided with a resin coil bobbin made by insert molding and integratedly assembled with a metal stator core. The stator core is arranged in and faces the rotor and forms a magnetic circuit therewith. The coil bobbin is arranged at the end side of the rotor. A holding portion is integratedly formed, the holding portion holds the urging member so as to urge the rotor to the bearing side. A curling base is fitted in. The curling base is formed such that a flat plate-shaped metal plate is rounded from outside of a winding wound by the electric coil bobbin in the circumference direction of the stator.
    Type: Application
    Filed: June 12, 2001
    Publication date: February 28, 2002
    Inventor: Eiji Mayumi
  • Publication number: 20010035693
    Abstract: A motor has a stator with a simplified structure having a stator section including at least two core pairs. Each of the core pairs includes inner and outer cores. Coils are wound around the core pairs. A case made of a magnetic material covers the coils in a manner that the case more securely comes in contact with the inner cores and the outer cores. The case is welded to at least the inner cores to securely form independent magnetic circuits.
    Type: Application
    Filed: February 6, 2001
    Publication date: November 1, 2001
    Inventor: Eiji Mayumi